双金属Ce-Mn/ZSM-5催化剂的制备及NH3-SCR脱硝性能研究  

Study on the preparation and catalytic performance of bimetallic Ce-Mn/ZSM-5 catalyst for selective catalytic reduction of nitric oxide by NH3

作　　者：梁彦正 王学涛[1] 张乾蔚 罗绍峰 周瑜枫 LIANG Yan-zheng;WANG Xue-tao;ZHANG Qian-wei;LUO Shao-feng;ZHOU Yu-feng(Department of Energy and Power Engineering,Henan University of Science and Technology,Luoyang 471003,China)

机构地区：[1]河南科技大学能源与动力工程系,河南洛阳471003

出　　处：《燃料化学学报》2020年第2期205-212,I0006,共9页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金项目(50806020);河南省科技创新人才计划(杰出青年)(114100510010);河南省自然科学基金项目(182300410256)资助。

摘　　要：采用浸渍法制备了铈锰复合氧化物分子筛催化剂(Ce-Mn/ZSM-5),在固定床反应器上考察不同Ce/Mn质量比对分子筛催化剂选择催化还原NO的影响,利用XRD、TEM、NH3-TPD、H2-TPR、in-situ DRIFTS等手段对催化剂进行了表征分析。结果表明,双金属改性的Ce-Mn/ZSM-5催化剂在NH3-SCR反应中表现出较为优异的催化活性,具有较宽的活性温度窗口。当Ce/Mn质量比为0.4时,催化剂具有最佳的脱硝效率,在265-465℃脱硝率均可达到80%以上,在370℃时,NO的转化率最高可达97.28%。锰和铈物种高度分散于催化剂表面,未改变ZSM-5的晶体结构,且构成协同作用。0.4Ce-Mn/ZSM-5具备丰富的酸性位、良好的氧化还原性能,该配比有助于催化剂的催化活性和稳定性的提高,在NH3-SCR反应过程同时遵循E-R机理和L-H机理。A series of Ce-Mn/ZSM-5 catalyst with different mass ratios of Ce and Mn was prepared by impregnation method,and the influence of Ce loading on denitrification performance was investigated in a fixedbed reactor. XRD,TEM,NH3-TPD,H2-TPR,in-situ DRIFTS were used to characterize the catalysts. The results show that the bimetallic Ce-Mn/ZSM-5 have a broad active temperature window. Especially,the catalyst with Ce/Mn mass ratio of 0.4 has the best denitrification efficiency,and the denitrification rate can be higher than 80% between 266 and 465 ℃,and up to 97. 28% at 370 ℃.Manganese and cerium species can be well dispersed on the surface of the support without changing the crystal structure of ZSM-5.0.4 Ce-Mn/ZSM-5 catalyst has abundant acidic sites,good redox performance. There are both E-R mechanism and L-H mechanism in NH3-SCR reaction.

关 键 词：脱硝 Ce-Mn/ZSM-5 NH3-SCR 反应机理 催化剂 

分 类 号：TK229.6[动力工程及工程热物理—动力机械及工程] X701[环境科学与工程—环境工程]